1. Field of the Invention
The present invention relates to novel compounds. More particularly, the present invention relates to novel lipoglycosides isolated from the plant Cerastium viscusum L. (Coryophyllaceae) Mississippi.
2. Description of the Prior Art
Crude extracts from plants have been used to treat diseases in humans for centuries. Recently, attempts have been made to extract and isolate pure tumor inhibiting compounds from plants. See, for example, S. M. Kupchan, "Novel plant-derived tumor inhibitors and their mechanisms of action," Cancer Treat Rep 60: 1115-1126 (1976). According to Kupchan, to obtain the desired extract, the plant is coarsely ground and subjected to extraction with a hot solvent in a Soxhlet apparatus. The temperature at which the extraction is conducted is substantially higher than room temperature but usually below 40.degree. C. The solvents most often used in such an extraction process includes petroleum ether and methanol. The so-obtained crude extract is subjected to further processing (such as fractionation) to yield an extract of high purity.
In an alternative method, the plant may be extracted in a percolation apparatus with an acceptable solvent. This extraction method is also conducted at a temperature substantially higher than room temperature but usually below 40.degree. C. The crude extract is also subjected to further processing to yield a product of higher purity.
As noted above, it is the normal procedure to extract plants using hot solvents. However, it is the present inventors' belief that extraction under heat is undesirable since some of the biologically active materials in the plant may be destroyed and lose its activity as a result of heating.
It has been known for several years that the species of Cerastium genus (Coryophyllaceae) are the source of flavoroid glycosides, fatty acids and the glycosides thereof. However, the activity of these glycosides against tumor cells has not been investigated as far as the present inventors are aware.